Overtraining

As training load increases there is an initial rapid improvement in fitness. Further increases produce diminishing returns until a optimum training is reached. Further training beyond this point produces less than optimal results until overtraining is reached when fitness is dramatically diminished.

Overtraining is a lack of recovery from training stress. The most serious type of overtraining is Overtraining Syndrome, but there are other categories. Each involves some imbalance between training and recovery, but with different outcomes. All levels of runner can experience any of the types of Overtraining, including Overtraining Syndrome.

Overtraining Syndrome is where the imbalance between training and recovery produces a decrease in performance and negative psychological changes. The negative effects of overreaching do not produce overall performance improvements through Supercompensation. (Main article: Overtraining Syndrome.)

Overuse is similar to TMTS, but is where a long term imbalance between training and recovery leads to injuries. Like TMTS, overuse does not have the mood changes that are indicative of Overtraining Syndrome. With Overuse passive recovery is often insufficient. (Main article: Overuse.)

Overload is a normal part of healthy, effective training. Overload has a short term performance decrement, but without the severe psychological and long lasting negative symptoms of Overtraining Syndrome[2]. Overload is sometimes called 'functional overreaching'. Overload can be recovered from in a few days[1].

1 Overtraining and Supercompensation

Exercise produces a temporary decrease in fitness, followed by a recovery and supercompensation.

With sufficient rest between workouts, fitness improves.

Without sufficient recovery time, the fatigue builds up until injury or overtraining syndrome occurs.